cn.lhfei.airqa.dao.support.Hibernate4DaoSupport.java Source code

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Here is the source code for cn.lhfei.airqa.dao.support.Hibernate4DaoSupport.java

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/*
 * Copyright 2010-2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package cn.lhfei.airqa.dao.support;

import java.io.Serializable;
import java.util.List;

import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.criterion.Criterion;
import org.hibernate.criterion.Projections;
import org.springframework.beans.factory.annotation.Autowired;

import cn.lhfei.airqa.common.Page;

/**
 * @version 0.1
 *
 * @author Hefei Li
 *
 * @since Apr 7, 2014
 */

public abstract class Hibernate4DaoSupport<E, I extends Serializable>
        implements AbstractHibernate4DaoSupport<E, I> {

    protected Hibernate4DaoSupport(Class<E> entityClass) {
        this.entityClass = entityClass;
    }

    public Session getCurrentSession() {
        return sessionFactory.getCurrentSession();
    }

    @Override
    public E findById(I id) {
        return (E) getCurrentSession().get(entityClass, id);
    }

    @Override
    public void saveOrUpdate(E e) {
        getCurrentSession().saveOrUpdate(e);
    }

    @Override
    public void delete(E e) {
        getCurrentSession().delete(e);
    }

    @Override
    public List<E> findByCriteria(Criterion criterion) {
        Criteria criteria = getCurrentSession().createCriteria(entityClass);
        if (criterion != null) {
            criteria.add(criterion);
        }
        return criteria.list();
    }

    @Override
    public Page<E> findPageByCriteria(Criterion criterion, Page<E> page) {
        Criteria criteria = getCurrentSession().createCriteria(entityClass);
        int count = ((Long) criteria.setProjection(Projections.rowCount()).uniqueResult()).intValue();
        criteria.setProjection(null);
        if (criterion != null) {
            criteria.add(criterion);
        }
        page.setTotalCount(count);
        int startCount = (page.getCurPage() - 1) * page.getPageSize();
        int endCount = startCount + page.getPageSize();
        criteria.setFirstResult(startCount);
        criteria.setMaxResults(endCount);
        page.setResult(criteria.list());
        return page;
    }

    public Criteria getCriteria() {
        return getCurrentSession().createCriteria(entityClass);
    }

    public void batchInsert(List<E> list) {
        Session session = sessionFactory.openSession();
        Transaction tx = session.beginTransaction();

        for (int i = 0; i < list.size(); i++) {
            session.save(list.get(i));
            if (i % 50 == 0) { //50, same as the JDBC batch size
                //flush a batch of inserts and release memory:
                session.flush();
                session.clear();
            }
        }

        tx.commit();
        session.close();
    }

    // PRIVATE FIELDS

    private Class<E> entityClass;

    @Autowired
    private SessionFactory sessionFactory;
}